[hhoover]

I would also suggest looking closely before shifting from where your experience lies. If you have anyone on the team that has any understanding of previous year's code, then I would suggest staying with C++. If you don't, then you basically have a rookie programming team and you need to look to them to pick the language because they'll have to do the work.
From my perspective - although >I< really dislike LabView - I have found that the kids seem to pick it up fairly well, and the online tutorials, etc. are good enough. Without a strong mentor and / or capable kids, any elaborate programming is out of the question, but drive train + basic control of specialty devices should be possible with at least one or two dedicated students.